Normally we use ssh for connecting to ur system over internet form other computer or mobile.When using ssh we will be having the ip address of the computer to which we need to connect .we set up a ssh server and we will be able to connect to this server using the ip to get a prompt to use.The main problem when u connect ur computer over internet is the dynamic ip problem.that is when the connection at ur computer is lost and reconnected u get another ip address and u don't know that one.
Using No-ip to get an static ip for the computer
Actually No-ip doesn't provide any static ip but binds our current ip to a host name so that when ever the ip is changed it automatically gets assigned to the host .thus by using the host name we a access the computer.
step1. Download the no-ip software form there site and install it-->> https://www.no-ip.com/downloads.php
step2.Make an account in the No-ip site and create a host name(which is free)
step3. now add the host name into the No-ip software in ur computer.First u need to use ur login id and password in the software then it will show ur host name .u can just select it.
Setting up ssh in windows
we can use freesshd for ssh services in windows.
just download it from www.freesshd.com and install it.setup an ssh server.set the listen interface to all.and create a user account .with authorization "password stored as sha1"and give the password. and turn up the ssh server
its done now we can use putty to check whether its working or not ..In putty give the host name as host name u registered in no ip and connect
to connect from mobile putty is available for android and Symbian also.in mobile putty we can give the host name and username which we have created.